[gitignore] ignore infer-deps-* generated by build-infer.sh

Summary:
This directory is created to trick opam into installing our dependencies even
if opam thinks it already did the job. If the user interrupts the build then
this directory can be left lingering around.

Reviewed By: mbouaziz

Differential Revision: D4779132

fbshipit-source-id: e47581a

.gitignore

@@ -17,6 +17,7 @@
 /_build
 /infer/_build
 /infer/tests/codetoanalyze/java/*/codetoanalyze
+/infer-deps-*
 _build_infer
 *.exp.test*
 *.test.dot